Street pi

A very unprecise Pi annotation (it does not give more than 2 digits) found on the streets of Lyon. Very concise anyway. The presence of a mathematical constant.

What is interesting is that the name "pi" (well, "π") is the first letter of the Greek words περιφέρεια which means "periphery". Perhaps, putting pi tags at the periphery of things would be a new trend in street art.